Money managers boosted net-long positions across 18 U.S. futures and options by 9.5 percent to 675,362 contracts in the week ended May 22, government data show. The Standard & Poor’s GSCI Spot Index of 24 raw materials reached a five-month low on May 23. A gauge of net positions for 11 U.S. farm goods surged 21 percent, the most since February, before agriculture prices tracked by S&P posted the biggest weekly loss in eight months.

The euro dropped to the lowest since July 2010 on May 25 after Catalonia’s president repeated his call for Spain’s central government to help regions access funding and S&P cut the credit ratings for five of the country’s banks. China’s biggest lenders may fall short of loan targets for the first time in at least seven years, three bank officials said, and the nation’s State Council refrained from backing Premier Wen Jiabao’s push to expand credit.

“It’s bit a surprising to see so much on the long side, because the trend is down in commodities,” said Walter ‘Bucky’ Hellwig, who helps manage $17 billion of assets at BB&T Wealth Management in Birmingham, Alabama. “We’re probably not going to see an extended rally until we get some type of monetary easing. Buying now is an aggressive move. You’re betting on a short-term pop from some sort of resolution in Europe.”

Agriculture Gauge

The S&P GSCI index fell 1.4 percent last week and is down 9.4 percent in May, heading for the biggest mostly loss since September. The S&P agriculture gauge tumbled 4.8 percent last week. The MSCI All-Country World Index of equities rose 0.7 percent, and Treasures slid 0.2 percent, a Bank of America Corp. index shows. The dollar rose 1.4 percent against a basket of six currencies, rallying for a fourth week.

Twenty of the 24 raw materials tracked by S&P dropped last week. Corn tumbled 9 percent, the most in a year, and cocoa slumped 7.2 percent, the biggest loss in 2012.

A political impasse in Greece, where voters rejected austerity measures in elections on May 6, has raised concern that country may leave the euro. Spain’s government is analyzing “with all caution” requests from regional governments to help them regain access to capital markets, Deputy Prime Minister Soraya Saenz de Santamaria said May 25. Catalonia is one of 17 semi-autonomous regions in the country.

Europe’s crisis risks deepening, damaging the world economy, the Paris-based Organization for Economic Cooperation and Development said in a report May 22.

‘Aggressive’ Stimulus

China’s Wen, in comments posted on the government’s website May 20, said the nation should put “stabilizing growth in a more important position” and increase lending to support construction. More “aggressive” stimulus measures will spur Chinese economic expansion and boost copper prices in the second half of the year, Morgan Stanley analysts led by New York-based Hussein Allidina said in a report May 21.

Copper inventories monitored by Shanghai’s exchange fell for a seventh straight week to the lowest since January. China is the world’s biggest consumer of industrial metals. Novelis Inc., the top global producer of rolled aluminum, said last week that doubling its output capacity may not be enough to meet rising demand from car makers.

“Where investors struggle at the moment is that they can see in the medium- to long-term it’s still a bull story,” said Jonathan Whitehead, the global head of commodities markets at Societe Generale SA. “Most of the reasons why commodities spent the 2000s going up are still there -- growing demand and increasing supply issues.”

$1.18 Billion

Investors pulled $1.18 billion from commodity funds in the week ended May 23, the fifth consecutive drop and the most this year, according to Brad Durham, a managing director at Cambridge, Massachusetts-based EPFR Global, which tracks money flows. Gold and precious metals outflows totaled $631.7 million, also the biggest exit this year, he said.

Speculators are bullish on wheat for the first time since September. Funds went from a short position, or betting on price declines, of 50,057 futures and options to a long holding of 7,026 in the week ended May 22, the CFTC data show. The gain of 57,083 contracts was larger than for any of the 18 raw materials tracked by Bloomberg. Prices fell 2.2 percent last week.

Export Sales

Slowing growth in China, the world’s biggest pork consumer, is eroding demand for grains used in livestock feed. In the week ended May 17, U.S. corn export-sales for delivery before Aug. 31, 2013, plunged 44 percent from a week earlier, the Department of Agriculture said May 24.

Gold wagers dropped for a third week to 77,318 contracts, extending a slump to the lowest since December 2008. Funds are bearish on copper prices for the first time since January, going to a net-short position of 2,808 contracts as of May 22, from net-long holdings of 4,833 a week earlier.

Nine of 18 analysts surveyed by Bloomberg expect the metal to drop this week and three were neutral. Traders were bearish for a second week, the first consecutive negative outlook since early April.

“There’s been a down shift in demand for a lot of commodities with the concerns over growth in China and Europe,” said Jack Ablin, the Chicago-based chief investment officer of BMO Harris Private Bank, which oversees about $60 billion of assets. “There are generally a lot of headwinds. We’re underweight in commodities and may go to zero.”